This invention relates to a method and apparatus for ensuring that the separate parts of a film-developing order in a commercial photofinishing laboratory are reunited after processing so that they can be delivered to the proper customer. More particularly, the invention relates to a method and apparatus that utilize an optical character reader to read identifying numbers printed on the parts of the order. The numbers are checked for correct matching to ensure that the correct parts of the same order are gathered together for delivery to the customer. Part of the invention is a method by which the detection system for initiating an alarm condition in the event of a mismatch is adjusted to compensate for the characteristics of optical character reading so as to filter out erroneous findings of a mismatch and reduce the number of false alarm readings that would otherwise occur.
In a typical commercial photofinishing laboratory customer orders are received in an envelope bearing the name and address of the customer as well as an identification of the delivery point, for example, a local drugstore or supermarket or other outlet at which the customer drops off the order. Typically, the order consists of a roll of exposed film that is to be developed at the photofinishing laboratory, printed as photographic prints according to the wishes of the customer, and then returned to the customer by way of the outlet at which the customer initially dropped off the order. Since the film must be removed from the envelope that it came in, in order to be developed, and since the envelope is the only source of information as to the customer and dealer name and address, it is necessary to maintain some correlation between the film and the envelope as they each proceed through the processing steps so that, at the end of the processing steps, the developed film and the prints made from it can be reunited with the envelope for proper return. It is also necessary, of course, to maintain correlation between the developed film and the prints made from that film to ensure that the proper prints are returned to the customer along with the developed negatives.
The primary method of maintaining correlation between the envelopes, film, and prints of a given photofinishing order has been to divide incoming work into manageable batches and then maintain a constant sequence of orders as they are processed so that, as long as the envelopes, film, and prints are removed from the batch in the same sequence in which they were entered, the correlation will be maintained. There are, however, several steps in the process, and requirements to remove damaged materials, which could lead to a change in sequence of one or all of the various parts of the order that would lead to a mixup in the final assembly of the parts of the order, if only sequence were relied upon for a match. It has been known for a long time to mark some identifying indicia on both the envelope and the film at the time they are received so that that indicia can then be checked prior to reassembly of the order and its return to the customer to ensure a proper match of film to envelope. Further, U.S. Pat. No. 4,574,692 to Wahli discloses a method by which the indicia for confirming a match of parts of the order is extended to marking of the prints so that a three-way match between envelope, film, and prints is checked upon reassembly of the order and prior to delivery of the order to the customer. As various matching methods and marking methods have evolved, the matching has been done at first by human operators and, more recently, through machine-readable indicators. Due to the accuracy with which they can be rapidly scanned, the state of the art has progressed primarily to a use of bar codes for encoding an identifying number on the film splice that holds various strips of film together during processing and on the order envelope, as well as sometimes on the reverse side of the prints belonging to an order. These bar codes are then scanned at some point prior to reassembly of the order to ensure that the correct parts of the order have been assembled.
While possible, as shown in U.S. Pat. No. 4,823,162 to Renn et al., it is difficult to accurately print bar codes on the splice tape as it is applied to each film order splice. Also, bar code printers of the type that would be necessary to achieve accurate reproduction of the code on the splice tape are expensive. Consequently, the industry has progressed in the direction of using preprinted barcoded splice tapes. The preprinted tapes add a significant amount to the overall cost of running the processing lab. Although the extra per-splice cost is small, the high volume that most commercial laboratories process, when multiplied by this small incremental cost, yields a large increase in the cost of laboratory operations. Bar code scanners suitable for film splice reading are also costly.
The advantage to using bar codes is a high percentage of accuracy of reading, which permits the use of a "hard coding" system; by this is meant that any mismatch reported as a result of the bar code scanning of the identifying numbers is regarded as correct information and leads to a shutdown of the system and a check by the operator. Even in the systems using preprinted bar-coded splice tapes and bar-coded identifying numbers on the order envelopes, a human-readable version of the bar-coded number is present in both those locations to allow for human backup of the system. Therefore, numbers that could be utilized in one or more locations for scanning by an optical character reader as an alternative to the bar code reading, are present but are not used. Of course, with optical character reading it is no longer necessary to have bar-coded identifying numbers on the splice tapes, thus removing the extra cost imposed either by preprinting or applying these numbers during splicing. Only the human-readable number need be applied.
One of the existing problems in using an optical character reader to read the identifying numbers on the various parts of the film order is that typically a higher percentage of misreads, as well as nonreads, occurs than in using a bar code scanner and, therefore, mismatches are indicated by the system when, in fact, the match is correct but one or more of the identifying numbers has been incorrectly read. Therefore, in order to implement a system using optical character readers, it is necessary to develop a system that accounts for the greater percentage of misreads that will occur when using an optical character reader on human-readable numbers and by adjusting the alarm system, which is triggered by apparent mismatches in the system, to reduce the number of false alarms that would otherwise interrupt the workflow of the processing lab.
A method of dealing with a false alarm situation is disclosed in U.S. Pat. No. 4,760,574, Budworth et al.; however, the Budworth et al. system is primarily concerned with readability of the bar code and treats any situation in which the bar code is not readable as presenting an error of equal weight. In the situation in which an optical character reader is used, it is necessary to consider not only nonreadability but, also, an apparent mismatch that may be caused not by an actual mismatch but a misread of the number by the system.